The study of viruses that evolved in the Australian indigenous flora is a neglected area. The south-west of Australia has a highly diverse, highly endemic plant flora, yet until our recent work, no significant work has been done on its viral component. Because of massive land clearance, especially since the 1940s, much of the remaining natural vegetation now lies adjacent to agricultural lands. This agro-ecological interface is the point where viruses that evolved in the indigenous flora for millennia meet crop plants, weeds of crop systems, and non-crop exotic plants. Similarly, viruses inadvertently imported with exotic plants encounter the indigenous flora and may grasp opportunities to expand their host range into the bush. Host change is major driver of virus evolution, and what exactly happens to viruses and their hosts at such interfaces is a focus of our research. We also have interests in persistent viruses of plants and their fungal symbionts. We are investigating how virus infection changes susceptibility of host plants to biotic and abiotic stresses. We have been successful in using the new high-throughput sequencing technologies to identify large numbers of described and undescribed viruses in wild and domesticated plants. Significantly, we have identified numbers of exotic viruses described from other parts of the world moving into Australia undetected by quarantine services in imported plant materials. Keywords: Flexivirus; Allexivirus; Potyvirus; Secovirus; Endornavirus; Partitivirus; Mitovirus, Megabirnavirus; dsRNA viruses; evolution; recombination; plant virus ecology; NGS; high throughput sequencing, diagnostics, biosecurity; agricultural viruses; plant-fungus-virus symbiosis